Improved Tightly Coupled Version of a Strapdown Gravimetric Navigation System of an Aircraft: Analysis of Specific Features

In this paper, we have presented the structure and improved functional algorithms for the aviation strapdown navigation gravimetric system of minimal configuration. We have considered a new scheme of the tightly coupled strapdown inertial navigation system (SINS) and global navigation satellite system (GNSS), which is based on combined use of the optimal Kalman filter (OKF) and ordinary least squares (OLS) method. The results of simulated modeling of the system's work are presented demonstrating improved accuracy of GNSS error correction, higher resultant accuracy of positioning and of vertical anomaly of gravity acceleration (GrA) determining.